This circuit is from a 1976 Motorola CMOS manual. It can be implemented with modern Darlingtons like those in the Texas TIP series. The load current depends only on the Darlington transistor.
This circuit multiplies the input voltage by 3 and can work with up to 12 V input. The current is a few...
This circuit was obtained in a Hands-On Electronics from the 90's. The circuit turns on one LED at...
This telegraph monitor was found in an American documentation for radio amateurs from the 1970s. The...